Continuity mistake: During Achilles and Hector's duel, in the wide shot Hector uses his shield to shove Achilles' spear tip down to the ground, beside his right foot while his left foot is way behind him. However, in the next close-up as the spear tip is still on the ground right behind Hector's left foot, his right foot comes forward to snap Achilles' spear.

Revealing mistake: After the Greeks break through the palace gates, Paris releases the first arrow into a soldier. As he begins to turn around, the bent dark arrow unbends at his neck at the start of the shot, before it becomes the straight lighter arrow.

Revealing mistake: At the start of the shot facing Patroclus (dressed as Achilles), as Hector's blade is up against his throat, then slices it, the ridged bottom of the fake latex throat that Garrett Hedlund (Patroclus) wears is visible, when he arches his head back.

Continuity mistake: When Priam, Paris, Glaucus, et al, arrive at the beach to see the Greek's 'Trojan' horse, the men who lie dead all over the sand change position. Particularly, in the first shot as it pans towards the horse, the two dead men in red lie on the sand in front of Priam a good distance away from the horse. In the next two close-ups of these men (the same two bodies), their positions are completely different. Then in the next wide shot, those two bodies are much closer to the huge 'Trojan' horse now.

Continuity mistake: After the Trojan rider finds the hidden Greek fleet, he is hit with three arrows in his torso. In the close-up there are two arrows above and one just below them, but in the wide shot the three arrows are aligned in a straight row.

Revealing mistake: When Achilles slices Hector's spear the two wood ends are jagged and the broken spear end that Hector later carries shows a jagged end on the wood. However when Achilles stabs Hector, as the spear protrudes from Hector's shoulder the wood end is perfectly even.

Continuity mistake: The cuts on Hector's face change and the one over Hector's left eyebrow actually changes direction, as well as other characteristics in many shots. When he shows his wife the tunnel, the top of the cut points towards the left side of his face, but when he stands at the gate and glances back at Helen, the top of the cut points up towards his right.

Continuity mistake: After Menelaus dies, during the Greek charge Hector spots Ajax doing his thing and the rolled white tourniquet around Ajax's leg wounds is clearly visible. When Hector rides toward Ajax, he promptly knocks Hector off his horse and the tourniquet is once again visible, only now it's wider and tied differently, and changes again within the following shots.

Continuity mistake: As Helen says, "They're coming for me. The wind is bringing them closer..." she leans on the large pillar, even as Paris walks over she stands beside it when they embrace. In the following wide shot, as Paris lets go of her, they are not standing in the same location as the previous close-ups.

Continuity mistake: When Menelaus bursts into Helen's room, as he confronts the handmaiden about her whereabouts, Menelaus' hair curl is in front of his shoulder when the shot faces the woman, but not when the shot faces Menelaus. The same thing happens with Paris when he is with Helen, with Glaucus when he says goodbye to Hector, when Hector speaks with Lysander at the armory and so forth. Throughout the film all the men's hair in front and back - its position, neat or not, curls or not, etc., noticeably changes between shots.

Visible crew/equipment: In the shot of Hector as he lies dying, there are shadows on his chest plate that are not his own, nor do they belong to Achilles - must be the camera.

Continuity mistake: When Paris and Menelaus face each other and then begin to fight, the shadows keep changing, and when the camera angles show each man's perspective, each man has his shadow to his own right hand side, even though they are opposite each other.

Factual error: Probably the most common mistake in all the ancient warfare movies like Troy. The thick leather armour that soldiers wear is almost impossible to pierce with such crudely sharpened swords but they always seem to pierce the armour with effortless ease.

Continuity mistake: At the start of the first battle when we see Achilles' soldiers penetrate the sands of Troy, Achilles throws a spear through a guys head. But if you look closely at the previous shot, the soldier's body is side-on, obviously so he can shoot the arrow, yet when it cuts to the spear going through the head, the soldier is completely facing Achilles.

Continuity mistake: In the middle of the film just after Hector has killed Menelaus, they run away, and on the far away shot, you can see they are some distance from Menelaus body, yet when it cuts to a close-up shot of them running they have barely passed the body.

Continuity mistake: When Briseis runs to Paris and shouts, "Paris! Don't!" in the wide shot, Achilles limps near the dead soldier on the grass. When Achilles is hit with the final arrow he drops to his knees and behind him an arrow lies on the ground (it is the 2nd arrow that hit him, which he pulled out and threw), opposite the dead soldier, which was much farther back in the previous wideshot of the grass.

Revealing mistake: Throughout the movie, especially in the scenes which take place in the Troy encampment, no matter how many times Achilles gets dirty in battle and then cleans up, there is always a small smudge on his left upper arm. In the right light, you can make out the distinctive, small, circular scar of a small pox vaccination right where that dirt smudge is - it's really quite distracting. Until 1972 in the US this was a common vaccination given to children.

Continuity mistake: Hector's sword slice,s Achilles's armor but the one shot shows the hit much higher up near the right shoulder than when we see a close up view and the cut is down by his ribs.

Continuity mistake: Close to the end of the film when we see Priam in Achilles' tent talking to him, in one shot you see Achilles looking down at his feet or away from him, in the following shot, he is looking directly at Priam.

Continuity mistake: While still in Sparta, when Helen stands up after Paris rubs her neck, the strap of her dress on her right shoulder is closer to her neck when she removes the dress, than in the previous shot.

More...

Due to the political situation in Iraq, the location for scale shots was moved from Morocco to Mexico, an ideal alternate choice with its broad beach, however, the rushed decision presented some obstacles. Coastal Mexico is an endangered turtle habitat, so to be granted permission to set up the Greek encampment and build boats on the large stretch of beach the film crew implemented their own turtle incubation nursery, thus releasing a multitude of turtles while on location in Mexico! They also did not have an accurate idea of the physical conditions of that particular beach. As it turned out that beach was very erratic and one morning about 100 feet of beach had washed away overnight, leaving Greek ships teetering precariously on the edge of the bank with the missing sand.